Film cartridges have existed, adapted for carrying endless film strips, which serve both as a container for the film and as a means for holding the film while it is projected. Such cartridges eliminate the need for threading the film prior to projection and for rewinding it after projection. An example of such a cartridge will be found in Mead U.S. Pat. No. 3,244,471, which uses the same general type of film threading and film storage chamber, as does the present invention.
Film cartridges of this nature, however, when used in large quantities, such as for educational purposes, must be inexpensive to manufacture. This requires the use of a minimal number of simple and inexpensive parts and a structure permitting ease of assembly. The present invention meets these criteria in that it has only three plastic parts, each of which is moldable. It turns out that this structure is not only considerably less expensive to manufacture, but is a better and more serviceable cartridge.